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How can two strings be concatenated?
How can I concatenate (merge, combine) two values?
For example I have:
12 Answers
12
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Deleting an element from an array in PHP
...d keys starting from 0.
Code
<?php
$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
//↑ Key which you want to delete
?>
Output
[
[0] => a
[2] => c
]
\array_splice() method
If you use \array_splice() the keys will be automatically r...
How to move one word left in the vi editor
...
Use b to move back one word.
Use w to move forward one word.
And here is a cheat sheet that might be useful for you:
Source: Graphical vi-vim Cheat Sheet and Tutorial
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Compare if two variables reference the same object in python
How to check whether two variables reference the same object?
6 Answers
6
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How to get method parameter names?
...k at the inspect module - this will do the inspection of the various code object properties for you.
>>> inspect.getfullargspec(a_method)
(['arg1', 'arg2'], None, None, None)
The other results are the name of the *args and **kwargs variables, and the defaults provided. ie.
>>>...
What does the red exclamation point icon in Eclipse mean?
...exclamation point icons" and "red exclamation mark decorators" and "red bang icons," no doubt because lots of plugins and programming-related tools use red exclamation point icons. So, to be clear, this is the one I mean:
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Use '=' or LIKE to compare strings in SQL?
...ee the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is much faster.
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
Let's say I have the following data.table in R :
3 Answers
3
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...nt of a vector or data frame is a duplicate of an element with a smaller subscript. So if rows 3, 4, and 5 of a 5-row data frame are the same, duplicated will give me the vector
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